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New dematiaceous species from Typha latifolia
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Transactions British Mycological Society NEW DEMATIACEOUS SPECIES FROM TYPHA LA TIFOLIA
J. L. MULDER Commonwealth Mycological Institute, Kew During an investigation on the biology of the fungal flora associated with Typha latifolia L. by Pugh & Mulder (1971) an undescribed dematiaceous hypomycete was isolated. It was more frequently isolated from the submerged areas of the leaf sheath, with its percentage frequency of occurrence decreasing towards the water surface. At this level and above it was not isolated. Occasionally it was found on the roots. Isolation methods, involving untreated and surface sterilized samples, indicated that the species is an internal colonizer. Plating out 6 mms sections on agar media proved a satisfactory method of isolation and lack of this method in the past could account for the species not being isolated before. Cellulose agar (Eggins & Pugh, 1962) was a very suitable medium for growth, as well as demonstrating cellulolytic ability. Optimum growth temperature was between 25 and 30°, and growth, although persisting, was greatly retarded at 35°. The helicoid nature of the conidia was observed best on slide cultures using potato-carrot agar. The species is being disposed in the genus Helicorhoidion, established by Hughes (1958) for two species, H. hotryoideum (Cke) Hughes and H. pulchrum (Berk. & Cd a) Hughes. It differs from these two species in that the coiling of the conidium very soon becomes irregular and obscures its helicoid appearance. Helicorhoidion irreguIare Mulder sp.nov, Coloniae in agaro 'potato-dextrose' effusae, olivaceo-brunneae vel atro-brunneae, Mycelium olivaceum vel brunneum, plerumque subrnersum, sparsurn aerium mycelium,
cinereum. Hyphae 2-4/Lm (plerumque 2-3/Lm) latae; laeves versus leviter granulares, Stroma ab est. Conidiophore macronemata vel diminuta, septata, 2-4!tm lata interdum latiora ad apices, pallide-olivacea vel brunnea, laevia vel leviter verruculosa. Conidia holoblastica,praecipue in hyphis submersis, interdum in aerio mycelio sparso, ellipsoidea, ovoidea, vel elongata, praecipue irregulariter helicoidea, similia dictyosporas, constricta ad septa, 29-42 '5 /Lmx 24-31 !tm; primo pallide olivacea, postea brunnea, Membrana brunnea vel fere atra, I !tm crassa, granularis. Ex foliaribus vaginis Typhae latifoliae, Attenborough Nature Reserve, Nottinghamshire, U.K., 21. i. 1970,J. L. Mulder 1M1 147546. Holotypus.
Colonies on potato-dextrose agar effuse, olive brown to dark brown. Mycelium olive or brown, mostly submerged, aerial mycelium, grey, sparse. Hyphae 2-4/lm (mostly 2-3/lm) wide, smooth to slightly granular. Stroma absent. Conidiophores macronematous or reduced, septate, 2-4 Ilm wide, sometimes wider at the apices, pale olive to brown, smooth to verruculose. Conidia holoblastic, mainly produced on submerged hyphae, Trans. Br. mycol. Soc. 61 (2), (1973). Printed in Great Britain
Nates and Brief Articles
10 ,lm
----------Fig.
I.
Helicorhoidion irregulare. Conidiophores and conidia.
Trans. Br. mycol. Soc. 61 (2), (1973). Printed in Great Britain
4°1
402
Transactions British Mycological Society
occasionally on the sparse aerial mycelium, ellipsoid ovoid to elongated, mostly irregularly helicoid, resembling dictyospores because of the tight coiling nature and the pronounced constriction at the septa, 29-42'5 x 243 I !tm; pale olivaceous at first, later becoming brown; wall brown to almost black in older conidia, I !tm thick, granular. REFERENCES
EGGINS, H. O. W. & PUGH, G.]. F. (1962). Isolation of cellulose decomposing fungi from the soil. Nature, London 193, 94-95· HUGHES, S.]. (1958). Revisiones hyphomycetum aliquot cum appendice de nominibus rejiciendis. Canadian Journal of Botany 36, 727-836. PUGH, G.]. F. & MULDER, ]. L. (1971). Mycoflora associated with Typha latifolia. Transactions of the British Mycolo/{ical Society 57, 273-282.
Trans. Br. mycol. Soc. 61 (2), (1973). Printed in Great Britain
Transactions British Mycological Society NEW DEMATIACEOUS SPECIES FROM TYPHA LA TIFOLIA
J. L. MULDER Commonwealth Mycological Institute, Kew During an investigation on the biology of the fungal flora associated with Typha latifolia L. by Pugh & Mulder (1971) an undescribed dematiaceous hypomycete was isolated. It was more frequently isolated from the submerged areas of the leaf sheath, with its percentage frequency of occurrence decreasing towards the water surface. At this level and above it was not isolated. Occasionally it was found on the roots. Isolation methods, involving untreated and surface sterilized samples, indicated that the species is an internal colonizer. Plating out 6 mms sections on agar media proved a satisfactory method of isolation and lack of this method in the past could account for the species not being isolated before. Cellulose agar (Eggins & Pugh, 1962) was a very suitable medium for growth, as well as demonstrating cellulolytic ability. Optimum growth temperature was between 25 and 30°, and growth, although persisting, was greatly retarded at 35°. The helicoid nature of the conidia was observed best on slide cultures using potato-carrot agar. The species is being disposed in the genus Helicorhoidion, established by Hughes (1958) for two species, H. hotryoideum (Cke) Hughes and H. pulchrum (Berk. & Cd a) Hughes. It differs from these two species in that the coiling of the conidium very soon becomes irregular and obscures its helicoid appearance. Helicorhoidion irreguIare Mulder sp.nov, Coloniae in agaro 'potato-dextrose' effusae, olivaceo-brunneae vel atro-brunneae, Mycelium olivaceum vel brunneum, plerumque subrnersum, sparsurn aerium mycelium,
cinereum. Hyphae 2-4/Lm (plerumque 2-3/Lm) latae; laeves versus leviter granulares, Stroma ab est. Conidiophore macronemata vel diminuta, septata, 2-4!tm lata interdum latiora ad apices, pallide-olivacea vel brunnea, laevia vel leviter verruculosa. Conidia holoblastica,praecipue in hyphis submersis, interdum in aerio mycelio sparso, ellipsoidea, ovoidea, vel elongata, praecipue irregulariter helicoidea, similia dictyosporas, constricta ad septa, 29-42 '5 /Lmx 24-31 !tm; primo pallide olivacea, postea brunnea, Membrana brunnea vel fere atra, I !tm crassa, granularis. Ex foliaribus vaginis Typhae latifoliae, Attenborough Nature Reserve, Nottinghamshire, U.K., 21. i. 1970,J. L. Mulder 1M1 147546. Holotypus.
Colonies on potato-dextrose agar effuse, olive brown to dark brown. Mycelium olive or brown, mostly submerged, aerial mycelium, grey, sparse. Hyphae 2-4/lm (mostly 2-3/lm) wide, smooth to slightly granular. Stroma absent. Conidiophores macronematous or reduced, septate, 2-4 Ilm wide, sometimes wider at the apices, pale olive to brown, smooth to verruculose. Conidia holoblastic, mainly produced on submerged hyphae, Trans. Br. mycol. Soc. 61 (2), (1973). Printed in Great Britain
Nates and Brief Articles
10 ,lm
----------Fig.
I.
Helicorhoidion irregulare. Conidiophores and conidia.
Trans. Br. mycol. Soc. 61 (2), (1973). Printed in Great Britain
4°1
402
Transactions British Mycological Society
occasionally on the sparse aerial mycelium, ellipsoid ovoid to elongated, mostly irregularly helicoid, resembling dictyospores because of the tight coiling nature and the pronounced constriction at the septa, 29-42'5 x 243 I !tm; pale olivaceous at first, later becoming brown; wall brown to almost black in older conidia, I !tm thick, granular. REFERENCES
EGGINS, H. O. W. & PUGH, G.]. F. (1962). Isolation of cellulose decomposing fungi from the soil. Nature, London 193, 94-95· HUGHES, S.]. (1958). Revisiones hyphomycetum aliquot cum appendice de nominibus rejiciendis. Canadian Journal of Botany 36, 727-836. PUGH, G.]. F. & MULDER, ]. L. (1971). Mycoflora associated with Typha latifolia. Transactions of the British Mycolo/{ical Society 57, 273-282.
Trans. Br. mycol. Soc. 61 (2), (1973). Printed in Great Britain